| The atmospheric particles are one of the hazardous pollutants in atmospheric environment which significantly impact climate changes, visibility decline, environmental damage(eg. acid rain, smog) and health hazard. This research focuses on the atmospheric particles of different functional areas and different seasons in Nanchang city. PM10 and PM2.5 were synchronous sampled in Jul-Aug 2007, Nov-Dec 2007 and Apr-Jul 2008, and the inorganic components and PAHs of PM10 and PM2.5 collected in summer and winter were comparatively analyzed to investigate the distribution characteristics and the rules of space-time changes. Source apportionment and the distribution characteristics of PAHs in PM2.5 indoors and outdoors were also studied in this paper.According to above analysis, the DAC (daily average concentration) of PM10 in summer was 149.09μg/m3, 0.99 times the concentration of National Secondary Standard; PM2.5 in summer was 88.03μg/m3, 1.35 times as much as American PM2.5 Standard; the DAC of PM10 in winter was 170.73μg/m3, 1.14 times of National Secondary Standard; and PM2.5 in winter 110.16μg/m3,1.69 times of American PM2.5 Standard. The DAC of PM10 and PM2.5 in summer were lower than that in winter. In different areas the pollution severity order of PM10 and PM2.5 was traffic roads (worse than), industrial zone, commercial mixing zone, residential zone and suburbs. The amount of PM2.5 was remarkably linear correlated with the amount of PM10, and a larger proportion than coarse particles in PM10, about 63%.Distinct space-time distribution characteristics of EAC (element average concentration) were shown in different functional areas. The EAC of urban areas was higher than that of the suburbs, while the EAC of the traffic roads and industrial zone was higher than that of the commercial mixing zone and residential zone. In PM10, the EAC of Al, Ca, Mg, Fe, Mn, Pb, Zn, Ti and Ni in winter were higher than those in summer, which was consistent with the tendency of DAC, and the EAC of S in summer was higher than that in winter, but no evident EAC changes of As, Cu and Cr with seasons were observed. In PM2.5, the EAC of Al, Ca, Mg, Fe, S, Mn, Pb, Zn and Ni in winter was higher than those in summer as the tendency of DAC; whereas no obvious EAC changes of As, Cu, Cr and Ti with seasons were found.The results of source apportionment illustrated that soil dust, burnt dust, building dust, vehicle dust and metallurgical dust were the dominant emission sources of PM10 and PM2.5 in atmospheric environment of Nanchang. The sources which made more contribution to PM10 also contributed more to PM2.5. Whether the concentrations of PM10 and PM2.5 reached the standard depends on soil dust, burnt dust and building dust, which become the emphasis of pollution control. The rank of pollution sources contribution ratio in the Summer and Winter simulated by BP network was the same as that simulated by CMB method, only varies in ratio numerical value. The preferable results proved feasibility of BP network in source apportionment.The HPLC method with diode array and fluorescence series detectors was established and corresponding chromatographic conditions determining PAHs of specific chromatographic column were optimized. The optimal emission wavelength was selected in 390 nm, and dual wavelength excitation was applied without complete separation of standard sample. The components of PAHs were separated efficiently in chromatographic column.The severity order of PAHs pollution in PM10 and PM2.5 was traffic roads (worse than), industrial zone, commercial mixing zone, residential zone and suburbs. The primary monomers of PAHs were 4-ring and 5-ring aromatics, 6-ring came next, 3-ring was least and 2-ring was hardly detected. The toxic risk rank was Bayi Square (more serious than), Luojiaji district, Old Campus of Nanchang No.2 Middle School, Rongchang district, and Xialuo Village. The contribution ratios of vehicle emission, coal burning, high-temperature heating and coking pollution to PAHs in PM10 were 33.7%, 18.8%, 13.0% and 18.0% respectively; the contribution ratios of various sources to PAHs in PM2.5 were 31.0%, 21.1%, 14.6% and 25.8% respectively. The results of factor analysis/multiple linear stepwise analysis conform to the energy structure of Nanchang city.The PAHs amount of Luojia district indoors and outdoors was higher than that of Bayi Square, Old Campus of Nanchang No.2 Middle School, Rongchang district and Liyuan district. The indoor PAHs of Bayi Square, Old Campus of Nanchang No.2 Middle School, Rongchang district and Liyuan district was correlated with outdoor PAHs, except that the indoor source in Luojia district contributes to PAHs as well. Compared with 3-ring and 4-ring PAHs, 5-ring and 6-ring PAHs were easilier accumulating in inhaled particles.
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